Lock-nut.



- J. IM'URDOOK.

LOOK NUT. APPLIUATION FILED DEC. 21, 1909.

Patented Mar. 14, 1911.

SR5 cm, wnsmnamn, o. c.

I TED STATES PATENT OFFICE.

EDWARD J'. MURDOCK, OF CHICAGO, ILLINOIS, ASSIGNOR TO AMERICAN LOCK NUT COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

LOOK-NUT.

escnoa.

To all whom it may concern:

Be it known that I, EDWARD J. MoRDooK, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and uselock nut of the type covered by United States Letters Patent No. 753,421, granted to A. L. Mowry, March 1, 1904.

In the practical use of lock nuts such as that described in the said patent to Mowry, it is necessary to place the finger over the end of the recess in the nut in which the locking key is placed when engaging the nut with a bolt or threaded bar, in order to prevent the said locking key from sliding out.

The object of my invention is to provide means for retaining the locking key in position without attention from the user of the device while the nut is being engaged with. the bolt. I accomplish this objectby magnetizing the locking key so that when it is placed within the recess in the metallic nut, it will be held therein against accidental displacement by magnetism. As a further means for accomplishing this object I provide a flange on the nut over one end of the key recess, so that should the engagement of the nut with the bolt tend to force the key axially with respect to the nut with sufiicient force to overcome the magnetic attraction between the locking key and nut, the flange over the recess will be engaged by the locking key and thereby positively prevent it from being moved axially within the recess.

In order to permit the use of the releasing pin, which is used to hold the locking key in the larger or deeper part of the recess in the nut while the nut is being removed, I provide an aperture for said releasing pin in said retaining wall. This aperture I place in that part of the wall which covers the part of the recess which has the lesser depth. I thereby provide a convenient and efficient means of guiding the releasing pin into the desired part of the recess without requiring care on the part of the user of the device.

My invention is more fully disclosed and its advantages made more readily apparent in the following specification and claims,

Specification of Letters Patent.

Application filed December 21, 1 909.

. Patented Mar. 14:, 1911.

Serial No. 534,277.

taken in connection with the accompanying drawings, in which- Figure 1. is an end view of a bolt or threaded bar with a hexagon nut in place thereon, and to which the aforementioned type of locking device has been applied, and to which my improvements have also been added. Fig. 2 is a sectional view of the same, taken on-the line 2, 2 of Fig. 1, and showing the locking key in place. Fig. 3 is a perspective view of the locking key. Fig. 4 is a-view of a form of releasing pin. Fig. 5 is an elevation of a hexagon nut with a portion broken away and showing the position of the retaining wall which constitutes the principal feature of my invention, and also to show a releasing device in position which in this case consists of an ordinary wire nail. The section portion of this view is taken on the line 5, 5 of Fig. 1. Fig. 6 is a sectional view of a modified form of nut, and Fig. 7 is a view similar to Fig. 5, showing the modification illustrated in Fig. 6.

Similar reference numerals refer to similar parts in the different views.

Referring more particularly to the drawings, it will be seen that I have chosen an ordinary hexagon nut to show the application of my improvements, but it should be understood that it may, of course, be applied to square nuts or to any form of nut, or other mechanical element, which may be attached to another element by means of screw threads and which it is desired to lock in position.

The reference numeral 15 designates the body of an ordinary screw threaded bolt or bar. Upon this is fitted the nut 16 in the usual manner.

A brief description of the type of locking device to which I have applied my improvements is as follows: The nut 16 is provided with a recess 17 which is cut into the interior of the nut, removing a portion of the threads and extending to a sufficient depth to properly receive the magnetized locking device 18. The recess or groove 17 has lateral sides 20 and 21 which are plane surfaces and are substantially parallel to radial lines which pass through the axis of the bolt. The said recess 17 has a bottom surface 19' which is inclined at a slight angle to the general direction of curvature of the outer edges of the thread. The locking device 18 has a form which in a general way is cylinthe threaded surface of the 'bolt 15.

drical and occupies the deeper portion of the recess 17.

It lies normally in contact with the bottom surface 19 of said recess an l rotation of the 'nut 30 in the direction of the arrow shown upon the nut in Fig. 1, which direction would be. that in which the nut would be moved to cause it to beunserewed from the bolt 15, will cause the more shallow portion of the recess 17 to ride upon the locking key 18 :and cause the latter "to be wedged between the inclined face '19-andthe body of the bolt 15. This wedging action will' cause a locking effect and prevent a V-shape, which are so spaced as to properly en age or mesh with the threads22 of the bot. Between the grooves a portion 22 of 'the' cylindrical surface of the locking key remains which provides a suflicient bearing area to properly contact with the inclined face'19at the bottom of the recess 17. The sloping walls of the V-shape circumferen- "tial grooves present the required extent of bearing'area for proper contact with the side walls of the threads 22. 7

In order to remove the nut 16 and with it the locking device 18 from the bolt, means must be provided for preventing the wedging action above described when the nut is rotated in such direction as to unscrew it from the bolt. This means may consist of a releasing pin such as shown at 26 in Fig. 4, or an ordinary'wirena'il 27 which is shown in Fig. 5 or other similar device, suchas a match, etc; By inserting this releasing device between the locking key '18 and the side-wall 21 of the recess 17, the locking key 18 is prevented from becoming'wedged between the surface'19 and the bolt 15.

Unless some means are provided forreleasmg the locking key in the recess, 1t 1S nec- M essary when screwing the nut on the bolt for the user to place a finger over the end of the recess 17 to prevent the locking key 18 from sliding out of the nut 16 when the latter is engaged with the bolt 15. In order to avoid the necessity of thus covering the slot117. by the finger, I magnetize the looking key, and may also provide the retaining wall 28 at the end of'said recess 17, and I preferably make the said wall'28 an integral 1. part of the nut 16. The said wall 28 may be of small thickness, as its purpose is merely to retain the'locking key 18 in, place and no great stress will ever act upon it. Athickness of metal equal to that of the wall 28 is carried around the bore of the nut in order to preserve a single plane surface and place on the bolt.

avoid steps or shoulders where the said wall is added. This thickened portion of the nut may bejoined to thebody of the same by the curved surfaces 30. i In this Way the appearance of the nut is improved.

In order to provide for the insertion of the releasing pin 26 or the wire nail 27, I provide the aperture 25 in the wall 28 in such position that the releasing pin may be guided into the space between the locking key718 and the wall 21 of the recess 17. The

aperture 25 will be the only visible portion of the locking device when the ,nut is in The retaining wall 28 preferably extends to the full depth of the threads and may engage the threads 22 ofthe bolt in the same manner as the other portion of the interior threads of the nut 16. This small portion of the thread may be cut at the same time that the balance of the thread in the interior of the nut is cut or tapped, no attention being required of themechanic in fitting this portion ofthe nutto the bolt.

The advantage of using a wire nail 27, or other device *havinga pointedv or reduced end, is apparent, as such device will readily find its place between the locking key 18 and the side wall 21 of the recess 17. In

using anu'nlocking pin of the form shown at '26 -with an abrupt or untapered end, there is some possibility of the end of said pinmeeting with the edge of the locking key .18. The further advantage of having a simple "aperture 25 in the nut in which to insertthereleasing pin is obvious, because theljuser does not have to exercise care in inserting the releasing pin.

While I have described more or less precisely the details of construction, I do not wish to be understood as limiting myself thereto, as I contemplate changes in form, and the proportionof parts, and the substitution of equivalents, as circumstances may suggest or render expedient without departing from the spirit of my invention.

What I claim is: i

1. The combination with a nut having a recess therein, one side of which opens into the bore thereof, of a magnetized locking key loosely located in said recess.

2. The combination with a nut having a recess therein, one side of which opens into the bore thereof, of amagnetized locking key loosely located in said recess, and a flange overlying one end of said recess to retain the key therein.

3. The combination with a nut having a recess-therein, one side of which opens into the bore thereof, of a magnetized locking key loosely located in said recess, and flanges forming permanent parts of the nut overlying the ends of said recess between whichthe locking key is interposed.

at. Thecombination With'a'nut having a recess formed therein, one side of which opens into the bore thereof, said recess having a substantially plane outer face deeper at one side than at the other, thereby forming enlarged and contracted portions, of a magnetized locking key consisting of an elongated cylindrical member loosely located in said recess and having a plurality of peripheral grooves formed therein, whereby said locking key will be wedged by the contracted portion of said recess against the thread of a bolt extending through the nut, and a flange on the nut overlying said recess to retain the key therein, said flange having a hole through the portion thereof overlying the contracted portion of the recess to permit the insertion of an unlocking pin.

5. The combination with a nut having a recess formed therein, one side of which opens into the bore thereof, said recess having a substantially plane outer face deeper peripheral grooves formed therein, whereby said locking key will be wedged by the contracted portion of said recess against the thread of a bolt extending through the nut, and flanges forming permanent parts of said nut overlying the ends of said recess to retain the locking key therein, one of said flanges having a hole therethrough over the contracted portion of said recess to permit the insertion of an unlocking pin.

In testimony whereof, I have subscribed my name.

EDWARD J. MURDOOK.

Witnesses:

GEO. L. WILKINSON, ANNY L. WALTON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

